Building Process

The Factory Building Process

Why build a home in a factory?

Probably the most famous person to start the manufacturing process was Henry Ford. He realized that you could produce products more efficiently on an assembly line rather then individually. He used economics of scale to produce products for less cost, not less quality. Simply put, the more units produced under one roof, the lower the costs.

So really, the major difference between site built homes and factory built homes is the building method, not the physical structure. Here are some of the economics of scale.

Materials and Supplies

Materials are purchased in bulk. Most factories do more business on lumber alone then a lot of lumber yards. This allows the factory to cut out the middle man. Site builders still have to purchase products through the lumber yard with their mark up.

Factories are able to warehouse large purchases at the point of production. Lumber purchased in trailer loads not truck loads. By storing materials in bulk at the point of production will also eliminate delays in construction due to material shortage.

Lower costs for labor can be used to handle materials because of the large warehouse. Generally site builders must use expensive trade’s people to handle the materials.

Labor

Site builders use a number of different trade’s people to complete the project. These trades’ people such as framers, roofers, plumbers, electricians, etc., must all be scheduled in an orderly manner to build a home. Most of them having to make return trips after each phase of construction is completed.

Factory builders have many homes in process. So it is only a short walk to the next home to be built. Many factories employ people that can do multiple trades. And because all of this is under one roof it’s easier to employ less skilled people and manage them more easily. All of which leads to being able to produce the same quality homes for less money.

Equipment

Building homes in a factory allows for equipment not used when site buildings homes. Large jigs, precision cutting equipment and cranes assist in the building process. These machines can make precision cuts and square framing better then a person can do with hand tools. Large walls can be built and moved into place by one or two people instead of half a dozen.

Engineering equipment also adds to the efficiency of building homes. Homes can be designed quickly and efficiently by in house engineers on CAD equipment. Site builders usually have to go to an outside architect or engineer which adds more cost. Also, building the same plans again and again adds to the efficiency of the production line.

Miscellaneous

There are a few other items that are to the factories efficiency. Because homes are built indoors, materials are never ruined by the weather nor are they lost due to theft.
Insurance is also cheaper. The factory working environment is safer and has more supervision.

What is the Construction Assembly Line?

Most facilities are very large, consisting of 100,000 – 200,000 square feet. This consists of office, warehouse, and production facilities. A scheduled production line process is used by injecting raw materials at different intervals to produce a finished product.

The first portion of the home to be built is the floor. This is built upside down so plumbing, heat ducts, and insulation can easily be added. To insure that the floor is square, it is built on a steel jig.

Next the floor is turned right side up. Large components, such as tubs, are set on the floor. Walls built on other jigs are set into place. Unlike site built construction, the walls are built from the inside out. The house will be framed and the walls only have sheet rock on them. The roof is set on the top in one section and the home is completely framed.

As the home moves down the production line, the electric is added to the exterior and interior walls. Insulation is put in the wall. Cabinets are hung on the walls and the finish trim is installed. Exterior sheathing, siding, windows, and shingles are some of the last items to be installed. At the end of the line, the home is wrapped in plastic to protect it from the weather and is ready for transportation to the new building site.